The broad goal of this project is to develop and apply computational tools for detecting, modeling and understanding biologically important sequence patterns, called motifs, encoded in the genome, in RNA and in proteins. Sequence motifs carry much of the information essential to the correct functioning of cells. For ex- ample, motifs in genomic DNA contain information that helps to regulate gene expression. Sequence motifs in RNA encode splice junctions and regulatory information such as microRNA binding sites. At the protein level, sequence motifs may participate in enzymatic binding sites, provide anchors for a protein structure or mediate posttranslational modifications such as phosphorylation by kinases. We model biological sequence patterns using statistical models that capture local sequence patterns while allowing for naturally occurring variability. Since 2011 more than 33,000 unique users have accessed the MEME Suite web portal, and the number of users has been steadily growing. As of June 28, 2013, the papers describing the MEME Suite have been cited 6827 times, according to Google scholar. In the proposed project, we aim to improve the core algorithms in the MEME Suite, add significant new functionality to the Suite, and improve the robustness, reliability and usability of software. In particular, we will significantly enhance the core motif discovery algorithm to scale to larger data sets, to identify new types of motifs, and t provide more accurate statistical confidence estimates. We will add functionality to the Suite to allow users to identify and characterize motifs associated with post-translational protein modifications. We will also carry out a series of software engineering and usability improvements that will greatly enhance the overall user experience. Our software can be locally installed or run remotely through our web portal to perform a diverse set of analyses on large, complex genomic and proteomic data sets. It is in widespread use by scientists around the world. We aim to continue to maintain and develop this software, facilitating scientific discovery and leading to insights into a wide spectrum of fundamental processes in molecular biology and human disease.